Fortran was old in the early 1980s, when I first taught it to myself for use on a research project. I'd taught myself BASIC, x86 assembler, and APL (for another physics course) by then. All the serious physicists were using Fortran though, for all their simulations.
My research project required use of the university mainframe for the big calculations, the 1000x1000 Markov matrices I was working on. I taught myself how to work on out-of-core code then as well, as well as exploiting symmetries inherent in my models.
My Ph.D. code was all written in Fortran, with a little Perl thrown in for good luck. 30+ years later, all of it works without a problem on my laptop/desktop machines.
I learned C in 1996 and C++ in 1997. The C code I wrote still works, though the C++ code needs special compilation options to be able to work.
I've not used Fortran in maybe 15 years now. I'm not up on the modern bits, I stopped using it professionally as F90 was becoming a thing.
I taught graduate HPC programming courses at my alma mater in the CS department, and gave the choice of Fortran or C to the kids. They blanched at the thought of using a nearly (at the time) 60 year old language. They correctly reasoned that learning the language would not help their employability.
Today, I use Julia for heavy computation. Python as a glue language, and C++ when required. I read the report, and I disagreed with the conclusions for a number of reasons, but what it comes down to is that many research groups in Physics/Chem still use Fortran, and aren't about to do the port to C/C++ due to funding. You can't get funding for this conversion. So codes will go on, students will learn what they need, and profs will keep publishing papers.
Moreover, this isn't the first, second, etc. time that people have predicted the death of Fortran. I heard this in 1990s as I was finishing up my Ph.D in theoretical/computational physics.
In 20 years or so, after I have (hopefully) retired, I'd bet that Fortran is still in widespread use, with Python following Java down the path to legacy. And the newer HPC language(s) will be quite happy to talk to Fortran.
I could be wrong, and I'm ok with it. But I doubt it.